Comparative studies of primate spatial cognition and memory. The first aim of this research is to determine some of the information that chimpanzees recall and convey about the nature, location and temporal availability of objects in outdoor environments. The research will obtain measures of recall that are independent of an animal's path of travel. Four chimpanzees will be tested. The animals are uniquely well-suited for studies of recall memory. They have learned arbitrary visual symbols (lexigrams) that refer to foods and other objects, and some can use the lexigrams outside the context in which they originally encountered the objects. The following method will be used to assess recall. An animal sees an experimenter place an object in an outdoor location. Later, in its indoor cage, the animal can indicate to uninformed person the type and location of outdoor location. Later, in its indoor cage. the animal an indicate to an uninformed person the type and location of the object. Delays between the cue-diving and response phases of the trial will range up to 4 weeks. The ability to recall information about features of the environment not present to the senses is important in human thinking, planning and communication, but to date there are almost no data on recall memory capabilities in non-verbal animals. The second aim of this research is to study the movements of capuchins, macaques and chimpanzees in computer-presented foraging, barrier and maze tasks. Tasks that an animal can solve in an outdoor enclosure will be modeled for presentation to that animal in a digital format. Animals will move a joystick to make a cursor hit a target on a computer monitor. In one study, barriers and/or targets will disappear as soon as the animal beings to move. Questions are how much detail the animal members about the positions of targets, landmarks, and barriers, and how efficient its route is. Each animal's route will be compared on a jump by jump basis to an optima routing. In a further study, barriers and targets will remain visible during trials. To assess planning ahead, eye movement swill be analyzed. Planning during initial solutions of novel mazes by maze-naive capuchins, macaques, and chimpanzees will be studies. The development of planning over a series of mazes will be examined, in accord with Bidell & Fischer's theory of the development of planning skills.